vertex 3/4 are solid choices , intel also works great if you are skeptical about OCZ (some people cannot phantom that they are reliable aswell)
however be sure to check benchmarks in regards to certain speeds samsung and crucial are "slower" ssd's compared to intel/ocz/corsair etc (not sure about gskill ssd's seems quiet around those so they aren't anything special likely)
samsung drives are overrated imo (stay away from the 840's they are hollowed out versions of the good average 830 prior of their line-up)

Please include motivations, "I would get a blablabla" really isn't helpful whatsoever.
The G.skill one seems to have launched in late September, so that'd be why it's unknown.

I really can't find a Samsung 830, only 840s.

what kind of motivation are you expecting in order to pick one card over the other? (speed, most reliable,price so many factors)
so many small differences between all those ssd's mixed with brand bias (which everyone has to some extend)